>>How about the use of the prefix "in". Why is "invisible" the opposite of "visible" but "inflammable" is not the opposite of "flammable".
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>Because, IIRC, "flammable" is a late addition. The right word is "inflammable," meaning that it can go into flames.
>
>Tamar

Ok that maybe so, but evenmore, if "inflammable" was the original word, the "in" prefix should make it the complete opposite of "can go into flames". Take these other word pairs for example, visible/invisible, competent/incompetent, active/inactive, complete/incomplete. As you know, there are many more.

Mike